Flag Marshal

Motorsport Flags

Green

Q 15.1. (i) Green flag – Waved: All clear, at the end of a danger area controlled by yellow flags. Also used to signal the start of a formation lap and shown at all posts during first lap of each practice session and during each formation lap.

(Appendix 40)
15.9. Green flag.  All clear, at the end of a danger area controlled by yellow flags.
It can also be used to signal the start of a warmup lap.

Which Means:

Always Leave Out After the Waved or Stationery Yellow Has Been Taken in

To Ensure That the Drivers That May Have Seen the Yellow “on the Way in” See the Green on the “Way Out”